Targets Associated to Immuno Processes - Antigen presentation

Targets Associated to Immuno Processes

GtoPdb receptor name: Linked to detailed view page for target. The target family is shown in brackets.

Process Association Comments: Comments provided by GtoImmuPdb curators giving more information about why the target is associated with Antigen presentation.

GO Associations: Specific, immuno-relevant Gene Ontology terms annotated against the target. These show the term, its ID and GO evidence code. GO annotations with GO 'IEA' evidence are italicized to to indicate that these are annotations applied by GO without curatorial judgement, so should be used with caution.

Immunopharmacology comments: General comments about the target's role in immunopharmacology, provided by GtoImmuPdb curators.

ACKR3 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. ACKR3 binds the chemokine CXCL12 (stromal cell-derived factor 1, SDF-1 which is also a ligand for CXCR4). ACKR3 is an atypical receptor in that it does not activate G-protein-mediated signaling but induces β-arrestin recruitment [56] ...

CCR2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CCR2 is discussed in relation to immuno-oncology in [2] ...

CXCR1 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR1 is discussed in relation to immuno-oncology in [2] ...

CXCR2 is one of more than 20 distinct chemokine receptors expressed in human leukocytes. Chemokines primarily act to promote leukocyte chemotaxis to sites of inflammation. CXCR2 is discussed in relation to immuno-oncology in [2] ...

PAR2 receptors have been reported to elicit pain and inflammation through a neurogenic mechanism of action, causing release of substance P, activation of NK1 receptors, and sensitization of TRPV1 voltage-gated ion channels. This action can be negated using a selective NK1 receptor antagonist (L732,138) or a TRPV1 receptor antagonist (capsazepine) [43] ...

Liver X receptors (LXR) are involved in the regulation of lipid metabolism and inflammatory responses. As such they are novel drug targets for cholesterol homeostasis (hypercholesterolaemia), inflammation, and with potential therapeutic effects in neurodegenerative diseases [127] ...

PPARγ agonists have anti-inflammatory effects. Full PPARγ agonists can cause undesireable weight gain, but partial agonists are devoid of this adverse effect and retain the anti-inflammatory effects of PPARγ modulation. The PPARγ agonist boosts the inflammatory phenotype of microglia and enhances their phagocytic capacity [64] ...

Autotaxin is up-regulated in many inflammatory conditions, including cancer, arthritis, fibrotic diseases and multiple sclerosis. The product of autotaxin activity, LPA, has proliferative, chemotactic and angiogenic actions. Inhibitors of the ATX-LPA axis are being investigated as novel pharmaceuticals [25] ...

Cathepsins B, H and L have become important therapeutic targets as their proteolytic activity has been implicated in several pathological inflammatory conditions, such as arthritis and periodontitis. Therefore, pharmacological inhibitors of these enzymes are in development as novel therapeutics.

Cathepsin S is expressed in the lysosome of antigen presenting cells (dendritic cells, B-cells and macrophages) where it processes the invariant chain-MHC-II complex (a chaperone protein that prevents premature peptide loading) inside antigen presenting cells and in this way controls antigen presentation. Due to this role in antigen presentation, inhibition of cathepsin S is expected to cause immunosuppression [110] ...

Ikkα is one of the catalytic subunits of the IκB kinase (IKK) complex, an upstream component of the NF-κB signal transduction cascade; NF-κB signaling being involved in propagating the cellular response to inflammation. IKK frees NF-κB from its inhibitory interaction with IκBα (inhibitor of kappa B), allowing NF-κB translocation to the nucleus where it modulates transcriptional activity. Additional functions of Ikkα beyond NF-κB activation are reviewed in [54] ...

CSK is an inhibitory regulator of Src family kinases, a family of protein tyrosine kinases indispensable to the initiation of signal transduction via ITAM-bearing immunoreceptors, and cytokine, growth factor, and pattern recognition receptor signalling. CSK phosphorylates an inhibitory tyrosine residue at the C terminus of Src kinases, leading to autoinhibition. CSK-induced Src kinase inhibition can also be mediated by binding to PEST family receptor tyrosine phosphatases [119] ...

Neutrophil elastase (NE) is a serine proteinase with broad substrate specificity. It is stored in azurophil granules within neutrophils and is involved primarily in host defence. However, in addition to attacking proteins on invading microorganisms, secreted NE also hydrolyzes proteins of the host extracellular matrix, such as collagen-IV and elastin, hence its role in degenerative and inflammatory diseases. NE functions as a promoter of γδ T cell activation via a protease-activated receptor (PAR1)-dependent mechanism [115] ...

Heme oxygenase (HO) is a rate-limiting enzyme in the catabolism of heme, catalyzing the oxidative cleavage of heme (Fe-protoporphyrin-IX) to render equimolar amounts of biliverdin, ferrous iron (Fe2+), and carbon monoxide (CO).

Heme oxygenase 1 (HO1) is a Nrf2-regulated gene, whose expression is upregulated as a cytoprotective mechanism in response to cellular stresses including inflammation, ischemia, hypoxia, hyperoxia, hyperthermia, or radiation.

HO1 has antioxidant, antiinflammatory, antiapoptotic, antiproliferative, and immunomodulatory effects in vascular cells, playing an important role in the prevention of vascular inflammation and atherogenesis (reviewed in [5] ...

Iκβ kinase β (IKK-2) is the pivotal enzyme component of the Iκβ kinase (IKK) complex, a complex crucial in regulating expression and activation of inflammatory mediators in airway epithelium. IKK-2 is an attractive target for development of pharmaceutical inhibitors with antiinflammatory action as treatments for asthma and chronic obstructive pulmonary disease (COPD) [12,15,102] ...

LYN is a Src family tyrosine kinase, expressed predominantly in hematopoietic cells, but also in neural, liver, and adipose tissues. LYN appears to function as a rheostat to modulate B cell signaling, and can be activating or inhibitory in action, depending on the B cell receptor and interacting protein complement present in particular cells [40-41,114] ...

Proteinase 3 (PR3), called myeloblastin when it was first identified, is an abundant serine protease found principally in neutrophil granules (but is also found on the surface of quiescent human neutrophils from peripheral blood). It is stored in the primary granules of circulating neutrophils alongside other cathepsin C-activated neutrophil serine proteases (NSPs), such as human neutrophil elastase (HNE), CatG, and NSP4. In pathological conditions it is thought that PR3 behaves to accelerate inflammation, by enhancing cytokine bioactivity, inactivating anti-inflammatory mediators and by promoting tissue injury (potentially by degrading extra-cellular matrix components like elastin, collagen, fibronectin, and laminins). In addition, imbalances between NSPs and their endogenous inhibitors can contribute towards pathological tissue damage, such as the damage associated with inflammatory lung diseases like chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. PR3 inhibitors are considered to be useful clinical candidates for anti-inflammatory drug development [63] ...

Small molecule inhibitors of Rab27a-JFC1 binding, termed Nexinhibs (neutrophil exocytosis inhibitors) demonstrate the druggability of Rab GTPases and inhibition of exocytosis of azurophilic granules in human neutrophils without affecting other important innate immune responses, including phagocytosis and neutrophil extracellular trap production. These thus have potential use as an inhibitor of systemic inflammation [55] ...

SYK plays a key role in coupling activated immunoreceptors to downstream cellular responses such as proliferation, differentiation, and phagocytosis. Mast cell, macrophage and B-cell activation (and release of inflammatory modulators) is disrupted by inhibition of SYK-mediated immunoreceptor signalling. Selective SYK inhibitors are being sought for a number of inflammatory conditions including rheumatoid arthritis, B-cell lymphoma and asthma/rhinitis [45,93] ...

Src family tyrosine kinases act as general modulators of immune cell signaling, playing diverse signaling functions, both inhibitory and stimulatory, in immunoreceptor and integrin signaling pathways [74] ...

All three TAM family receptor tyrosine kinases are involved in regulating inflammatory responses through a negative feedback loop. Specifically, AXL-Gas6 signalling is reported to induce autophagy in murine macrophages via inhibition of the NLRP3 inflammasome, an effect which reduces hepatic inflammation in a mouse model [49] ...

ITGAL associates with the beta 2 chain (ITGB2) integrin and CD18 to form the lymphocyte function-associated antigen-1 (LFA-1) complex. LFA-1 is crucial for leukocyte intercellular adhesion and costimulatory signaling in the immune system. Ligands for LFA-1 are the intercellular adhesion molecules (ICAMs) 1-3. ITGAL is the target of the withdrawn psoriasis monoclonal antibody drug efalizumab ...

TAP1 (ABCB2) and TAP2 (ABCB3) form a transporter that plays an important role in antigen presentation by major histocompatibility complex class I (MHCI) molecules in the adaptive immune response [100] ...

NRAMP1 / SLC11A1 appears to be involved in macrophage antimicrobial action against intracellular pathogens, and although its precise mechanism is not fully resolved, evidence indicates its involvement in the activation of phagocytes and synthesis of proinflammatory cytokines. Polymorphisms in the human SLC11A1 gene have been associated with susceptibility to several infections [19,103-104] ...

DC-SIGN is a pathogen-recognition receptor involved in initiating the primary immune response to various viral and bacterial pathogens, as well as antigen presentation and initiation of the adaptive immune response.

CD47 belongs to the immunoglobulin superfamily and is reported to bind membrane integrins and the ligands thrombospondin-1 (TSP-1) and signal-regulatory protein alpha (SIRPα). It is a ubiquitously expressed membrane protein that is a 'marker of self', and which is involved in self tolerance. Binding to SIRPα produces an anti-phagocytic signal. CD47 expression is hijacked by cancer cells to evade immune surveillance and macrophage-mediated removal. Anti-CD47 monoclonal antibodies are being investigated as novel immuno-oncology agents [72] ...

CD6 is a co-stimulatory molecule, predominantly expressed on lymphocytes and associated with autoimmune responses. CD6 interacts with activated leucocyte-cell adhesion molecule (ALCAM/CD166), found on antigen presenting cells. This interaction induces the production of proinflammatory cytokines [80] ...

Dectin-1 is a pattern recognition receptor involved in initiating the innate immune response upon recognition of various β(1,3)-linked and β(1,6)-linked glucans from fungi and plants. It mediates phagocytosis and the production of inflammatory mediators [20] ...

HSP90B1 is an endoplasmic reticulum chaperone required for proper folding and cell surface export of newly synthesized Toll-like receptor and integrin (CD11a, CD18 and CD49d) proteins. In its absence TLR responses are ablated, and there is no innate response to microbial stimuli [91] ...

IgE is being investigated as a molecular target in allergic inflammatory conditions such as asthma, allergic rhinitis and chronic spontaneous urticaria. One anti-IgE monoclonal, omalizumab, has already been approved for use in patients with asthma or chronic spontaneous urticaria. Omalizumab binds t ...

LILRB1 (CD85j) is a member of the inhibitory leukocyte immunoglobulin like receptor (LILRB) family (HGNC family 1182). It acts as an inhibitory immune checkpoint for B cell function. Ligands identified for LILRB include native MHC class I proteins, some HLA molecules, pathogen-derived ligands (e.g. from CMV, Dengue virus and some bacteria) and host immunomodulatory proteins such as S100 calcium binding protein A9 (S100A9; P06702; which also binds TLR4 and RAGE) [21] ...

LILRB1 (CD85j) is a member of the inhibitory leukocyte immunoglobulin like receptor (LILRB) family (HGNC family 1182). It acts as an inhibitory immune checkpoint for B cell function. Ligands identified for LILRB include native MHC class I proteins, some HLA molecules, pathogen-derived ligands (e.g. from CMV, Dengue virus and some bacteria) and host immunomodulatory proteins such as S100 calcium binding protein A9 (S100A9; P06702; which also binds TLR4 and RAGE) [21] ...

LILRB1 (CD85j) is a member of the inhibitory leukocyte immunoglobulin like receptor (LILRB) family (HGNC family 1182). It acts as an inhibitory immune checkpoint for B cell function. Ligands identified for LILRB include native MHC class I proteins, some HLA molecules, pathogen-derived ligands (e.g. from CMV, Dengue virus and some bacteria) and host immunomodulatory proteins such as S100 calcium binding protein A9 (S100A9; P06702; which also binds TLR4 and RAGE) [21] ...

LILRB1 (CD85j) is a member of the inhibitory leukocyte immunoglobulin like receptor (LILRB) family (HGNC family 1182). It acts as an inhibitory immune checkpoint for B cell function. Ligands identified for LILRB include native MHC class I proteins, some HLA molecules, pathogen-derived ligands (e.g. from CMV, Dengue virus and some bacteria) and host immunomodulatory proteins such as S100 calcium binding protein A9 (S100A9; P06702; which also binds TLR4 and RAGE) [21] ...